4778 Fishes. 



living on the globe, form three distinct subfamilies or genera to 

 be clearly and always distinguished by their dentition. To these 

 three genera or subfamilies he appropriates the names of, 1st, Salmo, 

 2nd, Forelle or Fario, and 3rd, Salmo Trutta or Trout, names not new 

 to naturalists, though new, perhaps, in their strict application to 

 the three subfamilies of the Salmonidse, long known and distinguished 

 in Britain as salmon, salmon or sea trout, and trout. These sub- 

 families then correspond with the arrangement of many European 

 naturalists who know them by the names of salmon, salmon-trout and 

 trout : the salesman, on the other hand, speaks of the Salmonidse as 

 of two kinds only, — with him what is not salmon is trout, — regard- 

 less of affiliations with species higher or lower in the scale, he looks 

 only to the market-value of the fish. 



To understand the question at issue between M. Valenciennes and 

 myself, t may first remark that the text of my friend is not clear ; the 

 engravings inaccurate and unworthy the high character of the work. 

 It is difficult, as I have experienced, to get artists to copy exactly 

 what is placed before them. The errors in the engravings alluded to 

 must be ascribed to the artists employed ; the obscurity in the text 

 M. Valenciennes, no doubt, will himself explain.* Proceeding on 

 principles directly opposed to those of M. Valenciennes, I select, as 

 the starting-point of the inquiry, the dentition of the young of the-Sal- 

 monidse ; one of the objects held in view being to ascertain whether it 

 be correct to say, in all cases, that " the adult salmon is to be charac- 

 terized by the persistence of certain vomerine teeth only ; the forelle 

 by the presence of others superadded to those of the salmon ; the 

 Salmo Trutta by the presence of a dentition wholly distinct from 

 both." The whole of my researches are opposed to this view, which, 

 although seemingly practical, is really not so. It may further facilitate 

 the clear apprehension of the object and results of these inquiries, 

 and their bearing on some important points in the Philosophy of 

 Zoology, if I, in the first place, lay before my readers the dental for- 

 mula arrived at by M. Valenciennes and subsequently the results of 

 the inquiries I have made into this matter, from which I think it will 

 be manifest to the scientific naturalist that the natural-history 

 arrangement of the Salmonidse adopted by M. Valenciennes is 

 inadmissible. 



1st. The true salmon, observes this distinguished naturalist, is cha- 



* Whilst occupied with the correction of the proofs of this memoir, I have just been 

 informed of the death of my most amiabte and esteemed friend. 



